George b



(No Model.)

G. B. WATSON. ELECTRIC INSULATOR.

Patented May 27, 1890.

\ Jf f 1 2 X 4 z 1/ i E f v WITNESSES: l/VKENTOR S 0, 16. WM fi gmi- HUNITED STATES PATENT OFFICE.

GEORGE B. \VATSON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE GOULD &\VATSON COMPANY, OF SAME PLACE.

ELECTRIC INSULATOR.

SPECIFICATION forming part of Letters Patent No. 428,979, dated May 27,1890.

Application filed August 12, 1889. Serial No. 320,538. (No model.)

To all whom it may concern:

Be it known that I, GEORGE B. VATSON, of Boston, county of Suffolk,State of Massachusetts, have invented certain new and usefulImprovements in Electric Insulators, of which the following is aspecification, reference be ing had to the drawings accompanying andforming a part hereof, in which- Figure 1 is a side elevation. Fig. 2 isa cen- IO tral vertical section. Fig. 3 is a plan view.

The object of my invention is the construction of a durable, efficient,and comparatively inexpensive insulator or device which may be insertedbetween an electrical conductor and [5 its support, and which shall havegreat strength, so that it may afford a secure support, and at the sametime shall serve to completely insulate the parts with which it isconnected below from those with which it is connected above; and itconsists in the device shown and hereinafter described, which comprises,essentially, a block or socket-piece having beveled sides, said sidesbeing surrounded by a layer of insulating material or composition, andbeing seated in a reverselybeveled recess or aperture formed in a blockor supporting-frame, said frame being provided with a cap for coveringor partially covering said aperture to retain the block or 0socket-piece in place, all as hereinafter more fully set forth.

My invention is more especially intended to be used in insulating thesupports of the overhead or line wires of electric railways.

3 5 Such supports require to be of sufficient strength to support aconducting-wire of considerable weight and to resist any downward strainof that wire, and also must be so constructed as to resist the upwardstrain exerted by the upward pressure of the springarm on the car as thecar passes the support. The insulating devices now in use for the abovepurposes, so far as known to me, lack efficiency, simplicity, anddurability, while 5 they are at the same time comparatively expensive.In my invention, one of the best forms of which now known to me is shownin the accompanying drawings, I have a lineinsulator in which the aboveobjections are reduced to a minimum.

I will describe my invention as embodied in the device shown in the saiddrawings, designating the various parts by letters'of reference.

A is a block or plug, preferably circular in 5 5 cross-section andhaving a flaring topthat is, having a top of the shape, or substantiallyof the shape, of the frustum of a cone inverted, and having its lowerpart cylindrical or with parallel sides. This lower part, however, isnot essential, as the flaring or conical sides may extend throughout thelength of the block, or they may be shortened and the cylindricalportion increased in length, the relative length of the conical portion,as also the angle of its sides, being comparatively unimportant,although I prefer the form shown, Fig. 2. To this block A is secured oneportion 0 of the line-support, preferably that to which the line-wire issecured, and for this purpose a threaded socket (shown at d, Fig. 2) isprovided in the lower end of the block or plug. As will be obvious,however, any suitable method of securing the support 0 to the blockmaybe employed.

E is a collar or support having a tapering aperture therethrough, thewalls of the apertu re being beveled to correspond substantially withthe flare of the block A, and the collar being in transverse section ofa shape corre- 8o sponding to the transverse section of the block. Thesmallest end'of the aperture in the collar is preferably of lessdiameter than the greatest diameter of the block, so that the block mayonly be inserted in the collar from above, (see Fig. 2,) and so that anydownward strain upon the block will be borne by the tapering or beveledcollar.

Between the block and the collar is a layer or mass f ofinsulating'material or compost tion, any suitable insulating materialbeing employed. This insulating material is preferably carried over thetop of the block A to more effectively insulate the same.

Two or more lugs or projections g are provided on the collar for thereception of bolts 71, secured by means of screw-nuts and passingthrough apertures in said lugs and in corresponding lugs or projectionson the capH, which extends over the collar and the inzoo closed block A,and serves to hold the block firmly within the collar. The edge of saidcollar is preferably provided with a down- \vardly-prejecting flange 2',which serves to shed moisture and to protect the insulation.

The precise method of securing the cap to the collar is obviouslyunimportant so long" as the two are firmly secured together and so thatthey may be readily detached when that is desired. The space between thecap and the block A should for the best results be filled with theinsulating material.

For the purpose of securing the device to the upper portion J of theline-support I make the cap somewhat thicker in the central portion, sothat it may be provided with a threaded socket into which the rod Jmaybe screwed; but the precise method of securing the device to thesupport J is not essential.

To prevent rain or moisture from interferinc with the insulation, theusual skirt 7 or bell-shaped projection may be provided, and

is preferably secured to or made integral with the collar E, as shown.

I am aware of Letters Patent No. 8,Jr-l9, dated October 14, 1851, whichshow an insulating' device adapted to be secured to a post or similarobject, and having a protectingcover to which the other parts are notsecured, but within which they are retained by securing the insulator inposition, and I do not claim such a device.

\Vhat I claim is An insulator comprising a block having an enlarged endand beveled sides, a collar having a tapering or beveled aperture, a capsecured to said collar, and an interposed layer or mass of insulatingmaterial separating said block from said collar and cap, substantiallyas shown and described.

1EORGE l3. XVATSON. \Vitnesscs: Y

Wu. A. MACLEOD, ROBERT \VALLAOE.

